An inverse voltage-to-current conversion circuit for providing a current that is inversely related to an input voltage is disclosed. A first input terminal and a second input terminal receives the input voltage between the first and the second input terminals. A voltage-to-time converter circuit provides a time indicator pulse signal with a pulse width related to inverse magnitude of the input voltage. A time-to-voltage converter circuit provides a voltage indicator signal having a magnitude based on the pulse width of the time indicator pulse signal. A voltage-to-current converter circuit provides a current indicator signal having a magnitude proportional to the voltage indicator signal—the current indicator signal being inversely related to the magnitude of the input voltage.

Embodiments of the invention are directed to a current sensor that includes a current controlled oscillator circuit configured to receive an input current and to provide an output signal having an output frequency which is dependent on the input current. The current sensor further includes a feedforward circuit configured to adapt a reference voltage of the current controlled oscillator in dependence on an instantaneous current value of the input current.

Embodiments of the invention are directed to a current sensor that includes a current controlled oscillator circuit configured to receive an input current and to provide an output signal having an output frequency which is dependent on the input current. The current sensor further includes a feedforward circuit configured to adapt a reference voltage of the current controlled oscillator in dependence on an instantaneous current value of the input current.

In one aspect, an analog-to-digital converter circuit includes a transimpedance amplifier including a feedback capacitor electrically connected between an inverting or a non-inverting input of the transimpedance amplifier and an output of the transimpedance amplifier. The circuit includes an hourglass switch electrically connected on a first side to a first input and a second input, and electrically connected on a second side to the non-inverting input and the inverting input. A fine input current to the transimpedance amplifier is received at the first and second inputs. In a first mode, the hourglass switch electrically connects the first input to the non-inverting input and the second input to the inverting input, and in a second mode, the hourglass switch electrically connects the second input to the non-inverting input and the first input to the inverting input.

In one aspect, an analog-to-digital converter circuit includes a transimpedance amplifier including a feedback capacitor electrically connected between an inverting or a non-inverting input of the transimpedance amplifier and an output of the transimpedance amplifier. The circuit includes an hourglass switch electrically connected on a first side to a first input and a second input, and electrically connected on a second side to the non-inverting input and the inverting input. A fine input current to the transimpedance amplifier is received at the first and second inputs. In a first mode, the hourglass switch electrically connects the first input to the non-inverting input and the second input to the inverting input, and in a second mode, the hourglass switch electrically connects the second input to the non-inverting input and the first input to the inverting input.

An AC voltage detection device has a rectifying circuit configured to rectify an AC voltage output from an AC power source, a voltage-pulse conversion circuit configured to convert a rectified voltage rectified in the rectifying circuit to a first pulse signal having a period shorter than a half of a period of the AC voltage, a pulse transmission circuit configured to perform signal transmission with electrical insulation by converting the first pulse signal to a physical signal other than an electrical signal and converting the physical signal to a second pulse signal being an electrical signal, and a controller to which the second pulse signal is input. The controller calculates the voltage value of the AC voltage from a characteristic value of the second pulse signal.

An AC voltage detection device has a rectifying circuit configured to rectify an AC voltage output from an AC power source, a voltage-pulse conversion circuit configured to convert a rectified voltage rectified in the rectifying circuit to a first pulse signal having a period shorter than a half of a period of the AC voltage, a pulse transmission circuit configured to perform signal transmission with electrical insulation by converting the first pulse signal to a physical signal other than an electrical signal and converting the physical signal to a second pulse signal being an electrical signal, and a controller to which the second pulse signal is input. The controller calculates the voltage value of the AC voltage from a characteristic value of the second pulse signal.

Provided is a power detection circuit for tracking a maximum power point of a solar cell. The power detection circuit includes: an average voltage extracting unit which extracts an average voltage V.sub.PV,LPF from an external voltage V.sub.PV input from an external energy source; a ripple voltage extracting unit which extracts a ripple voltage including current information of the external voltage V.sub.PV from the external voltage V.sub.PV; a voltage-time converter which generates a ramp voltage V.sub.RAMP changing at a predetermined rate and converts the average voltage V.sub.PV,LPF and the ripple voltage into corresponding time information t.sub.1 and t.sub.2 based on the ramp voltage V.sub.RAMP; a time-digital converter which converts the time information t.sub.2 for the ripple voltage into a digital code t.sub.2 [n:0]; and a time multiplier which multiplies the digital code t.sub.2 [n:0] and the time information t.sub.1 for the average voltage V.sub.PV,LPF to output a specific voltage value.

Provided is a power detection circuit for tracking a maximum power point of a solar cell. The power detection circuit includes: an average voltage extracting unit which extracts an average voltage V.sub.PV,LPF from an external voltage V.sub.PV input from an external energy source; a ripple voltage extracting unit which extracts a ripple voltage including current information of the external voltage V.sub.PV from the external voltage V.sub.PV; a voltage-time converter which generates a ramp voltage V.sub.RAMP changing at a predetermined rate and converts the average voltage V.sub.PV,LPF and the ripple voltage into corresponding time information t.sub.1 and t.sub.2 based on the ramp voltage V.sub.RAMP; a time-digital converter which converts the time information t.sub.2 for the ripple voltage into a digital code t.sub.2 [n:0]; and a time multiplier which multiplies the digital code t.sub.2 [n:0] and the time information t.sub.1 for the average voltage V.sub.PV,LPF to output a specific voltage value.

A processor includes a plurality of voltage droop detectors positioned at multiple points of a processor. The detectors monitor voltage levels and alert the processor if a droop event has been detected in real time. Multiple droops can be detected simultaneously, with each detected droop event generating an alert that is sent to a processor module, such as a clock control module, to act based on the detected droop. Each detector employs a ring oscillator that generates a periodic signal and a corresponding count based on that signal, where the frequency of the signal varies based on a voltage at the corresponding point being monitored.